John nutting farrar



v J. N. FARRAR. MEOHANISM POR'SEPARATING TEETH.

(No Model.)

Patented Apr. 8,1890.

Ira/970307 UNITED STATES PATENT OFF CE.

JOHN NUTTING FARRAR, on NEW YORK, n. v. o

MECHANISM FOR SEPARATING TEETH.

SPECIFICATION forming part of Letters Patent No. 425,067, dated April 8, 1890.

Application filed June 4, 1889- Serial No. 313,102. (No model.)

To all whom it may concern:

Be it known that I, JOHN NUTTING FARRAR, a citizen of the United States, residing in the city of New York, county and State of New York, have invented new and useful improvements in adjustable apparatus to aid dentists in operating upon the teethviz., Mechanism for Separating Teeth; and I hereby declare that the following specification is a sufficiently clear description thereof to enable other persons skilled in the art to make and use the same, reference being had to the accompanying drawings.

My invention has for its object the easy separation of teeth and the retaining of the rubber dam to facilitate the operation of plugging cavities in teeth. I attain these objects by the improved mechanism illustrated in the accompanying drawings, which belong to and constitute a portion of this specification, and in which- Figure 1 is a perspective view of the mechanism. Fig. 2 is a view of parts detached. Fig. 3 is a view of one of the levers, the other being shown in Fig. 2; and Fig. 4 is a view of said levers pivoted together, parts being broken away.

The apparatus is preferably made of steel or other metal nickel plated, and includes a device having two arms or levers A A, pivoted together like an ordinary pair of tailors shears. The arms A A are provided near their adjacent extremities at one end with apertures to receive detachable separatingclamps. These are indicated by the letters 0, 0', and P, and are provided with suitable dowel-like projections or pins to fit said apertures, or with equivalent fastening devices, and they are variously shaped to adapt them to different positions or conformations of teeth. The opposite extremities K K of the device are provided, the former with a groove G and the latter with a rib K, to fit, respectively, a groove and rib formed on the edges of a wedgeshaped piece, which latter fits loosely on a screw S, flattened at one end and perforated to receive the pivot that passes through A A.

A screw-nut T on the rod S is provided for forcing the wedge toward the pivot and spreading the ends K K, thereby in operation causing the clamps fitted in or on the opposite ends of A A to securely embrace any object lying between them, as will be readily understood.

J J indicate different forms of holes to receive various clampsor separators.

I denotes a gum-guard which is adapted to v be screwed into a'suitable hole in one of the members A or A, and when in use rests upon the opposing surface of the tooth to prevent the creeping down of the clamps upon the gum, and thereby causing pain to the patient.

I is a similar guard screwed into an arm A and used for a like purpose, but made longer and so bent that the free extremity will rest loosely in a hole in the opposite arm, and I is a guard on arm A, having a loop to engage theend of an arm A or A.

As shown, the ends of the arms AA are provided with holes of different shapes. A section of similar arms provided with apertures'for receiving the clamp-separators is shown at F in Fig. 2. Y

0 indicates a clamp provided with an extension L, that can be inserted in a corresponding aperture.

Of the devices for holding the wedge in the proper plane I prefer a pin such as illustrated combined with a spring-loop F. The latter device is very efficient, but is liable under some conditions to be in the way. It can be applied to either side K or K. of the implement. The wedge WV can be entirely removed from the screw. It can also be'turned to engage the pin with an opposite side, if such side is suitably grooved. WVith such devices as the pins or as the spring-loop it is not necessary to provide ribs and grooves on the faces of the wedge and parts K I as they will hold the wedge in the proper plane and obviate any tendency to turn about the screw that is to rotate about its axis.

I am aware that various devices for separating teeth and detachable clamps that slip like ferrules over arms have been proposed by others, and devices of this character are not broadly of my invention.

Having thus described my invention, whatl claim, and desire to secure by Letters Patent, is as follows:

1. The device for holding separators or clamps, consisting of two pivoted members having apertures at one end to receive said clamps and mechanism consisting of a wedgeshaped piece, a screw-bolt passing therc- 4-. The eombimuion of the pivoted arms through and secured between said members with the clamps, gum-guards, grooved and or arms, and a nut fitted to screw upon the ribbed Wedge, screw, and wedge-operating bolt and jam the wedge between the arms to nut working on the screw, substantially as 5 force toward each other their opposite ends described. 20

and the clamps secured therein,substantially 5. In combination with the arms pivoted as described. to each other and adapted to receive clamps 2. In combination with the pivoted arms, at one end thereof, the wedge \V, situated at the wedge provided with a groove and a rib, the opposite end, and mechanism for forcing IO the arms being correspondingly grooved and the wedge toward the pivot, substantially as 25 ribbed, substantially as described. described.

3. The combination of the pivoted arms, JOHN NUTTlNG FARRAR. the clamping-pieces, a gum-guard, and mech- Witnesses: anism for forcing the clamping-pieces upon A. T. \VILSON,

I 5 the teeth, substantially as described. A. I). llELLFELD. 

